Is there any big difference in the Proform body versus milling and smoothing the choke horn off my 750? Maybe even a bigger carb all together? Nothing really wrong with how the engine runs, just curious about making it run better and to its fullest potential.

 

The proform main body has downleg boosters.
And swappable air bleeds.
The HP series holleys have these boosters too.
If you don't mind putting in the work, you can kick up the cfm flow of your carb nicely.

A K&N stub stack will get you cabout 90% of the flow improvement of cutting off the air horn and radiusing the inlet edges. There is different models of stub stacks for different purposes ( air cleaner height, choke horn etc)

 

IMHO,the Proform body is the best buy in carb accessories on the market.
I can't see anyone milling your choke horn and smoothing it out for less than the $150 price of the proform.Plus you get the added tuning benefits of the air bleeds.

 

Theres more flow to be picked up by working the base plate than there is with milling the choke horn. Mill the shafts and install a set of countersunk or buttonhead screws is good for more CFM. I don't have the flow sheets but I'll find them. We took a 650 and did the base plate work and flowed it. Then milled the choke horn off of another carb with a stock baseplate. The baseplate picked up a ton, and the choke horn picked up just a few (aound 10) but together they flowed the same as the carb with the choke horn still on it. I'll have to dig up the sheets tomorrow.